1. Field of the Invention
This invention relates to a dust collecting apparatus for removing dust generated by a sander as it removes material from the surface of a workpiece.
2. Description of the Prior Art
Examples of a conventional dust collecting apparatus for removing dust generated by a sander are disclosed in Japanese Utility Model Publication No. 13674/79 and German "Auslegeschrift" No. 1938350.
Conventional dust collectors require special parts in addition to those used in a conventional sander. For example, one type of conventional dust collecting apparatus requires a separate pipe or the like, which serves as a dust passage to lead dust to a fan from a sander unit having perforated sandpaper. In an alternative type of conventional dust collecting apparatus, separate parts divide the machine into interior and exterior portions to form a dust passage to lead dust from the center of the sander unit to the fan. Such types of machines are equipped with a central bearing in the sander unit and thus require special dustproof means for the protection of the bearing.
The additional special parts required for conventional dust collecting apparatus constitute a disadvantage of conventional machines because the structure of such machines becomes complicated. The more complicated structure increases the production cost and also the weight, while decreasing the mechanical reliability and ease of handling of the sander.